Answer:
(A) $500,000
Step-by-step explanation:
Given formula for finding the cost ( in dollars ) to remove p percent of a certain pollutant,
[tex]C=\frac{100000p}{100-P}[/tex]
If P = 90,
[tex]C=\frac{100000\times 90}{100-90}=\frac{9000000}{10}=900000[/tex]
If P = 80,
[tex]C=\frac{100000\times 80}{100-80}=\frac{8000000}{20}=400000[/tex]
∵ 900000 - 400000 = 500000,
Hence, it will cost $500,000 more to remove 90% of the pollutant from the pond than it would cost to remove 80% of the pollutant,
Option '(A)' is correct.